Source of Ceiling water damage

New Member

Hi everyone. I am new to the forum and also a new homeowner. I have a small 2 bedroom house in southern CA that I purchased January of this year.

When I bought the house a general contractor did a home inspection and pointed me to problems with bubbling and paint cracking/fraying on the ceiling in the master bedroom bath. At first I thought the water damage on the ceiling was from a leaking roof or skylight based on the pattern. The general contractor said the damage was more likely due to inadequate ventilation in the bathroom.

The bathroom is quite open and has an open wall that channels into the rest of the master bedroom. The master bedroom is about 175 square feet not including the master bath. I would think there would be water damage elsewhere if it was caused by steam from the shower. The only thing I can think of is the steam tries to rise by the 1st skylight. There is a heat lamp in the small toilet room (it's like a closet with a toilet in it). There is a vent but there is no fan/exhaust.

I've attached some photos. Does anyone have any thoughts on whether the water damage is from steam from the shower as indicated by the contractor, or is it likely from a leaking skylight? I am going to inspect the skylight again further once I can borrow a big enough ladder, but the contractor had looked last December and didn't indicate a leak there. It hasn't rained much at all this season and I can push the bubbling a little but I can't really tell if its very wet underneath it. I've not used the master shower much at all because I wasn't sure if the steam was causing the problem. I also make sure to use the heat lamp in the toilet room when the master shower is being used.

My biggest problem is my significant other complaining about not being able to use the master shower whenever she wants. Thanks so much in advance.

Contractor retired

If it was moisture from the shower you expect to see droplets form near the skylight on a cool day. I have seen water get behind the paint before and is has alway been a leak above, the staining shows up later. But that's just my experience, I would still install a fan for that shower. The heat lanp ois a nice touch but it really adds moisture to the air faster than normal.

Well-Known MemberSponsor

Former or present skylight leak: spray with hose to check or just recaulk.
Former bathroom moisture problem: repair and watch?
Present bathroom moisture problem: check with moisture meter a bit after a shower.

Well-Known Member

Get Zen grasshopper and think like water ...The bubbling seems to be below the skylight closest to the shower. Condensation from steam might occur with colder air in the light box leading to droplets trailing downward along the ceiling. You can scrape and re-paint with a good quality interior semi-gloss.

I recently re-did three bathrooms which had been originally painted with lousy flat interior (one sprayed coat). The paint developed curling along the path of the steam because the lady liked to take long showers (in three bathrooms -- don't ask) with the windows closed.

You need aggressive ventilation too. Maybe you should position it below the first skylight? Might not be feasible but you need to evacuate the moisture before assuming there is a leak.

Attached Files:

Retired decorating contractor

OP,
It looks like a poor repair job that is now failing. Since there is no staining it is likely not from a leak. It may have been done just prior to the sale. Redo it properly, prime, the top coat with a quality product designed for damp environments. If it recurs you will need some sort of powered ventilation.

New Member

Thanks so much everyone. I am going to climb on the roof this weekend and spray with a water hose and see if I can determine anything.

There is definitely bubbling that I can push in but I can't tell when it happened and it felt dry when I touched it last week. It could have possibly come from well before the previous owner was in the home. The previous owner had the home for 4 years and the bubbling and cracking on the paint was definitely there when I bought it.

I haven't ever seen any drips of water on the floor the few times we got rain this season earlier in the year towards January and February.

The paint definitely should have been done with semi-gloss. I'm going to first see if I can find a leak on the roof. Thanks everyone for the useful advice.

New Member

Thanks so much everyone. I am going to climb on the roof this weekend and spray with a water hose and see if I can determine anything.

There is definitely bubbling that I can push in but I can't tell when it happened and it felt dry when I touched it last week. It could have possibly come from well before the previous owner was in the home. The previous owner had the home for 4 years and the bubbling and cracking on the paint was definitely there when I bought it.

I haven't ever seen any drips of water on the floor the few times we got rain this season earlier in the year towards January and February.

The paint definitely should have been done with semi-gloss. I'm going to first see if I can find a leak on the roof. Thanks everyone for the useful advice.